Strong Construction: the USB volume control is made of shell shaft, equipped with breathing light and come with USB cable.With one key mute function, when you are listening to music, just press the knob, it will stop at once and back to music when you press again.This volume control knob supports for Win10/8/7/Vista/XP/for Mac, once you insert it to your computer, it can start to work; with OTG cable, it can also work for phone.(Note: some phones can't work, for replacing Android native sound control program , such as for Samsung.).A great volume control tool for watching videos, playing games, even will be the best volume controller for activities, wedding, meeting, celebration and so on.Simple Operation: turning the knob to turn up and down volume, press the knob to make it mute, press down the knob and turning to adjust volume more quickly; keep pressing the knob for 8s, it will enter night mode, breathing light will stay on.This USB volume adjuster can directly control the computer operating system volume. It also can adjust volume by OTG leads to connect mobile phone, car computer, set-top box and other Android devices.Disconnect the o lead or malfunction, it wouldn't affect the sound quality and make a noise.Switchable USB cable is common with usual mobile phone charging cables.Blue breathing light is interacted with operation. Soft blue light indoor and in the evening and you can adjust it lighting or closing.Big chassis, metal body, HIFI appearance, stable using, without movement, one finger operation, quick reaction and multifunction.Connections:Insert the volume regulator into the computer USB port; the o output device directly inserts into the computer 3.5mm earphone hole.(As long as the sound is from computer, built-in speakers, external speakers, earphone, power amplifiers, hotel mixer or 7.1 surround speakers can be used.)Support operation systems: for Windows (XP/Win7/Win8/Win10, etc); for Mac; Linux; Vista; Android.Colour: BlackMaterial: Aluminum alloy(The color of the characters on the product is random Not accept the designation)Package Contents:1 x Volume Controller1 x USB cableOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.